In recent years, in organic electroluminescences, various solar cells, touch panels, mobile phones, electronic papers, and the like, transparent electrodes using a transparent conductive film are being eagerly investigated.
For example, organic photoelectric conversion or electric-optical conversion devices represented by organic thin-film solar cells are usually fabricated by laminating materials on electrodes composed of a transparent conductive film. As for the transparent conductive film, though various conductive films such as metal thin films, metal oxide thin films, conductive nitride thin films are being investigated, metal oxide thin films are the mainstream at present because they are chiefly capable of making both light transmission properties and conductivity compatible with each other and are also excellent in terms of durability. Above all, in particular, tin-doped indium oxide (ITO) is widely used in view of the facts that it is well balanced between light transmission properties and conductivity and that it is easy for achieving the formation of a fine electrode pattern by means of wet etching with an acid solution (Patent Document 1).
On the other hand, there is proposed a sheet in which a metal-made fine mesh or grid is formed on a transparent base material such as PET (Patent Document 2). There is a possibility of utilization of such a sheet as a transparent electrode because its translucency and conductivity can be controlled according to a design of the mesh (rate of opening determined by a pitch or line width).
Now, in the case of laminating layers composed of an organic element material, electronic devices have hitherto been manufactured by a vacuum vapor deposition method or a dry process analogous thereto, a wet process represented by coating, or a lamination process via a pressure-sensitive adhesive layer (Patent Document 3). In such a lamination process, transparent electrode films and transparent conductive films having stickiness have been desired; however, the conventional transparent conductive films involve a problem on a balance among transparency, stickiness, and low resistivity.
Accordingly, it has been proposed to use, as a conductive component in a conductive adhesive composition, a conductive organic polymer compound such as polythiophene or derivatives thereof. More specifically, it has been proposed to manufacture an electronic device by a lamination process via a pressure-sensitive adhesive layer containing a conductive organic polymer compound (see Patent Document 4 and the like).
However, in the lamination process via a pressure-sensitive adhesive layer containing a conductive organic polymer compound, the utilization was limited in an element application in which cleanliness and uniformity of an interface are important. In addition, there was involved such a problem that the performance of an electronic device is lowered, for example, the conductivity of the pressure-sensitive adhesive layer is low, the carrier injection efficiency at the laminate interface is lowered, an adhesive force of an interface is low, and the like.